Robertson



(ModeL) 4 e v J. H. ROBERTSON.

H P A R G E L E T G I H P A R G 0 T U A No. 420,833. Patented Feb. 4,1890.

7/////////// raw UNITED STATES PATENT OFFICE.

JAMES H. ROBERTSON, OF BROOKLYN, ASSIGNOR TO THE W'RITING TELE- GRAPH OOMPANY, OF NElV YORK, N. Y.

AUTOGRAPHIC TELEGRAPH.

SPECIFICATION forming part of Letters Patent No. 420,833, dated February 4, 1890.

graphs of the class inwhich the marking point of the receiving-instrument moves in obedience to electric currents varied in force.

by the movements of the style or tracer of the sending-instrument; and it consists of the several combinations of parts hereinafter described and claimed.

In the accompanying drawings, which form a part of this specification, Figure 1 is a side elevation of an apparatus embodying my invention. Fig. 2 -is a plan view of the two groups of conducting-strips and resistances. Fig. 3 is an end view of the receiving-stylus, controlling-magnets, and armatures of Fig. 1. Fig. 4 is an enlarged detail view of the sending stylus or tracer. Figs. 5, 6, 7, S, and 9 represent modifications, in which Fig. 9 is a side view of one of the two magnets and armatures shown in Fig. 8.

Referring to the drawings, 5 indicates a group of conducting-strips separated by suitable insulating material and constructed to present a smooth flat surface for writing with a stylus or contact-maker. Between every two adjacent strips a resistance, as 4, is introduced, which preferably consists of a coil of wire, but may have any other approved form. The several resistances are all connected together and to the wire 3 and battery 2, grounded at 1. A second group 15, in which the conductingstrips are arranged at right angles 'to those of the first group, is placed in proximity to the latter, as indicated in the drawings, and said strips are connected to resistances 14, as in groups 5, and to the ground at 11, through battery 12, by wire 13.

The stylus or contactqnaker, ith which the characters are traced on the two groups of conducting-strips,consists of a handle 6, held in the hand of the operator, and of an arm 16, secured thereto, but insulated therefrom. The handle 6 of the stylus has con- Application filed February 3, 1885. Serial No. 154,795. (Model) tact-point 6, which makes contact with group 5, and is connected with conductor 7,

cally-movable spring-pressed point or pin 21,.

which permits a certain amount of vertical movement of the arm withoutbreaking the contact of the pin with its group of strips.

To still further guard The said pin or point is suitably guided in the arm, and is caused to project by a spring 22, fastened at one end to the pin and at the other to the arm, said spring serving also to electrically connect the said parts.

The handle or contact-point 6 of the stylus or contact-maker, which operates, in fact, as a circuit-closer, is connected by a conductor or wire 7 with an electro-magnet' 8, the two poles of which act upon a light armature 23, pivoted in front of the same. Said armature carries a small and light electro-magnet 18, arranged at right angles and similar in form to electro-magnet 8, and also an armature, as

25, therefor. The latter, as illustrated, is pivoted to a support or arm secured to the side of its own electro-magnet. The armature is held in its normal position, and is retracted to said position when its magnet ceases to be energized by an adjustable spring 26. Armature 23 is likewise connected to an adj ustable spring. (Not shown.)

The arm 16 of the stylus is connected by conductor or wire 17 with the electro-mzignet 18, which operates the armature 25, the latter moving at right angles to armature 23.

To the armature 25 is loosely attached a pencil, pen, or other marking-instrument 28, which rests upon a strip of paper 37, on which the message is to be reproduced at the sending-st-ation, a similar apparatus being located at the receiving-station. The duplication of the reproducing apparatus in the same circuits is to enable the operator to see what he has outlined on the conducting-strips, and a record to be preserved of the matter transmitted. The said inarking-inStrument passes through suitable guides 27 and rests on the paper by the force of gravity.

The operation of the mechanism so far described is as follows: The movement of the stylus across the strips of group 5 and at right angles thereto will gradually decrease the strength of the current circulating in the coils of electromagnet 8,because of the gradual introduction of resistances into its circuit, and its retracting-spring will therefore gradually pull the armature 23 away from the said magnet, thus causing the stylus to make a straight line across the strip or ribbon of paper. IVhile the armature 23 has thus moved across the paper the armature 25 has not altered its position relatively to its electro-magnet, for no variation in the resistance of its circuit has taken place. The armature 25 was of course attracted the instant the stylus made contact with the two groups of strips, but it remained in its attracted position during the said movement of armature \Vhen the contact-maker is moved to cross the strips .of group 15 at right angles, the resistance of the circuit of electromagnet 18' is varied, and it will be understood without further explanation that a mark parallel with the strip of paper and at right angles to the mark first referred to is recorded on said strip.

It should be noted that if straight lines are traced by the sending-stylus the recorded lines produced by the described mechanism are also straight lines and are not curved to any extent. In fact, all lines or characters are and must necessarily be correctly reproduced thereby. This is essential to correct reproduction, especially of phonographic or stenographic characters. hen the contactmaker is moved in a diagonal direction, or in i any direction other than at right angles to the strips, the strength of the current is varied in both circuits, and the marking-instrument will be controlled by the movements of bot-h armatures and will trace a diagonal or curved line, as the case may be.

The paper 37, which constitutes the stationary recording-surface upon which the marking-pen reproduces the letters or characters, is preferably in the form of a ribbon. It remains stationary while the marking-pen is in operation, and in the interval is fed forward step by step in the following manner: In the circuit controlled by the arm 16 of the stylus an electromagnet 19 is included, whose armature 29 operates the pawl 30 of the escapement of a clock-work mechanism consisting of a coiled spring and gear -wheels, which mechanism revolves one or both of a pair of pressure-rollers 31 and 32, between which the paper passes. \Vhen the arm 16 is in contact with the strips of group 15, the circuit is closed and the armature 29 attracted; but

stylus I place an electroanagnet. 9, whose armature is located above the marking pen or pencil and from which the latter is suspended by a fine cord,wire, or thread 43. The length of the suspending-cord is so adj ustedthat the marking-pen will rest on the paper when the armature is attracted,but will be lifted therefrom upon the breaking of the circuit when the armatureis retracted by spring 35. \Vhen, therefore, both contact-points of the stylus are lifted from the two groups of strips, the paper is fed forward, and at the same time the marking-instrument is lifted. It will be noticed that if only the contact-point (3 breaks its circuit the marking-pen is lifted, but the paper remains at rest. This construction permits the dotting of letter i, the crossing of letter t, and the proper formation of other letters which in ordinary writing require two or more independent strokes of the pen for their formation. In tracing the letter t, for

instance, the contact'point 6' is lifted after the body or stem of the letter has been formed, and then again brought into contact with the paper at the right place to trace the line for crossing the stem of said letter.

Generally, in writing the sending style or tracer is lifted after the tracing of every letter; but two or three letters may be traced in succession without breaking the circuits. A greater number than that, however, unless of small size, cannot well be traced in. the limited field provided by the strips.

The drawings show only the instruments at the sending-station, but those at the re ceiving-station are duplicates thereof, the conductors or wires 10 and 20 leading thereto.

When the sending-stylus or tracer is not in use,its contact-points are inserted in the sockets 4:1 and 42, forming a pen or stylus supporter or receiver, which are made sufficiently deep to hold said stylus in an upright position and are connected to ground, so that the two circuits will be closed when the markingstylus i. e.,the sendi.ng*stylus-of the other station is in operation.

The mechanism for operating the marking pen or receiving-stylus can be modified more or less. In Fig. 5 the marking-pen is attached to armature instead of to armature 25, as in Fig. 1. It is not directly attached to said armature, but to a frame or support 38, piv-' oted thereto, which frame is connected by a flexible or a rigid connect-ion 39 with. the armature 25, so that the frame can partake of the movements of the latter. An adjustable spring, as 86,18 employed to return the parts to normal position when the circuit is broken. This modified mechanism also ef fects the correct reproduction of the lines traced.

In Figs. 6 and 7 the construction shown in Figs.1 and 5, respectively, is modified so that both electro-magnets are stationary, thus relieving armature 23 of the weight of electro-magnet 18. WVhile these modifications possess this advantage, they have the disadvantage that the armature is shifted laterally with reference to the poles of its magnet; but as this lateral displacement is but little relatively its effects can in practice be disregarded.

In Figs. 8 and 9 the frame 38, for carrying the stylus, is pivoted to armature 23, and is connected bya flexible or rigid connection 39 with the end of armature 25, which latter (see Fig. 8) is hung by a universal joint 40 from a stationary support. In this case, also, armature 25 can move laterally with reference to its electro-magnet, although it is not directly pivoted to armature 23, as in Figs. 6 and 7.

Itwill be observed that oneof the functions of the transmitting-stylus is to act at times as a member of a switch-that is to say,when it is lifted from the conductin -strips, where it is used for transmitting tothe pen-supporter, it switches the transmitter out of circuit and switches in the receiver,.the latter result being effected by the co-operation of the stylus with said pen-supporter. The switch or switch mechanism consists, therefore, of the stylus,

which acts as the moving member of the switch, the conducting-strips of the transmit ter, and the pen-supporter, the said conducting-strips being connected to the transmitter and said pen-supporter being connected to the receiver, so that in moving the stylus from the former to the latter the transmitter is switched out of and the receiver is switched into the circuit.

I am aware of United States Patent No. 217,588, to Edward A. Cowper, dated July 15, 187 9, and what is therein shown and described is hereby disolaimed.

I am also aware of English Patent No. 1,242

of 1879, and what is therein shown and described I hereby disclaim.

I am aware of Patent No. 5,957, dated Desockets said stylus is held when not in oper ation, substantially as described.

2. In an autographic telegraph, the combination, with a transmitter and a receiver located at one station and the electrical connections constituting the line to another station, of a pen-supporter arranged to connect the receiving-instrumentto the line when the pen is inserted therein, substantially as set forth.

3. In an-autographic telegraph, the combination, with a transmitter and a receiver located at one station and the electrical connections constituting the line to another station, of a pen supporter co-operating with the pen of the transmitter, and necessary electrical connections, substantially as set forth.

4. In a writingtelegraph system, the combination, with the receiver and a pen-supporter, of a switch for switching the receiver into circuit, and necessary electrical connec tions, substantially as described.

5. In a writing-telegraph system, the combination, with a transmitter and a receiver located at one station and electrical connectionsconstituting the line to another station, of a switch and a pen-supporter co-operating with the pen to connect the receiver to the line, substantially as described.

In testimony whereof I have hereunto subscribed my name.

JAMES H. ROBERTSON.

Witnesses:

N. J. EURO/HELL, S. E. REYNOLDS. 

